1. Field of the Invention
The present invention relates to an oxygen abosorption composition which has functions of absorbing oxygen, inorganic gases, organic gases, moisture in some case and the like without requiring moisture in absorbing oxygen, and which is used for the preservation of metallic part items, electronic part items, electric part items, precision part items, magnetic/optical part items, ornamental jewellery, weapons, aircrafts, automobiles, glass, rubber products, photographic films, foods, pharmaceuticals pressed dried flowers, paintings, antique documents, unearthed articles from ruins, and the like items and matters. In addition, the present invention pertains to an oxygen absorption composition which is suppressed in heat generation accompanying the reaction with oxygen and also is enhanced in safety in the case of its disposal or transportation.
2. Description of Ralated Arts
There have heretofore been known, as an oxygen absorbent, a metallic powder, catechol, ascorbic acid and the like each as a principal component. However, since the above-mentioned oxygen absorbents require moisture in absorbing oxygen, the oxygen absorption system needs to be highly humid, thereby limiting the object of preservation in the oxygen absorption system. On the other hand, there is proposed in Japanese Patent Application Laid-Open No. 29741/1992 (Heisei-4), a composition as an oxygen absorption composition which does not require moisture in the case of oxygen absorption. There is disclosed therein that an unsaturated aliphatic hydrocarbon and/or an unsaturated aliphatic compound are used as principal components. According to the working examples disclosed therein, there are used unsaturated fatty acids or fats and oils comprising unsaturated fatty acids as unsaturated aliphatic compounds, and polymers in liquid form of hydrocarbons having unsaturated groups as unsaturated aliphatic hydrocarbon. However, the unsaturated fatty acids or fats and oils comprising unsaturated fatty acids involve the problems in practical application that a large amount of gases are generated after the absorption of oxygen and that the gases are malodorous. On the other hand, the polymers in liquid form of hydrocarbons having unsaturated groups involve the problems that the liquid hydrocarbons are difficult to be supported on a carrier at the time of production because of their usually high viscosity. There is described that the polymers in liquid form of hydrocarbons having unsaturated groups are mixed with unsaturated fatty acids or fats and oils comprising unsaturated fatty acids to bring the resultant mixture to a low-viscosity principal component. Nevertheless, the problem still remains unsolved in practical application thereof in that a large amount of gases are generated causing marked malodor because of the unsaturated fatty acids or fats and oils comprising the unsaturated fatty acids that are contained in the resultant mixture, thus necessitating a large amount of a gas absorbent to absorb the generated gas. In addition, there is proposed in Japanese Patent Application Laid-Open NO. 115776/1993 (Heisei-5), a deoxidizing film comprising an ethylenically unsaturated hydrocarbon and a transition metal as a catalyst. In general, however, the above-proposed deoxidizing film involves the problem that a considerably long time is required for completing deoxidization.
In general, many oxygen absorbents are accompanied by heat generation at the time of deoxidization (oxygen absorption). Thus, when such an oxygen absorbent is allowed to stand in the atmosphere, the temperature thereof is suddenly raised as the case may be, whereby delicate care is often made necessary in storage or disposal thereof, especially in the case of accumulation of large amount of oxygen absorbents.